CGRG Bibliography of Canadian Geomorphology
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Author : Baltzer, A., Cochonat, P. and Piper, D.J.W.
Date : 1994
Title : In situ geotechnical characterisation of sediments on the Scotian Slope, eastern Canadian continental margin
Publication : Marine Geology
Issue : 120:
Page(s) : 291-308
Abstract
A seabed 2-m-long cone penetrometer and coring system (Geotechnical Module) has been used at 17 stations in four transects on the Scotian Slope to characterise in situ shear strength and induced pore pressure on several different types of late Pleistocene and early Holocene failure. Study sites were selected using the SAR high-resolution deep-towed acoustic system equipped with a digital 160-190kHz sidescan sonar and a 3.5kHz subbottom profiler. Several distinctive types of "geotechnical signature" were recognised from plots of cone resistance and induced pore pressure with depth in the sediment. Normally consolidated sediments show a progressive increase in cone resistance with depth (to about 75kPa at 2 m subbottom). Holocene surficial muds show spectacular apparent over-consolidation, reaching a peak of 250kPa at about 50cm subbottom and then decreasing down to 1.5 m. This overconsolidation is associated with Zoophycos burrows. Late Pleistocene sediments exhumed by bedding plane slides show strong true overconsolidation consistent with the original depth of burial inferred from high-resolution seismic stratigraphy. Debris flows show only a slight shear stress gradient with depth (40-45kPa over 0.5-1 m subbottom) with under-consolidation due to remoulding of sediment.
Bibliography of Canadian Geomorphology